Cam-actuated grip-finger wrench



Aug. 16, 1949.

J. B. ALEXANDER CAMACTUATED GRIP FINGER WRENCH Filed Feb. 1, 1946 INVENTOR JOHN B. ALEXANDER ATTORNEY Patented Aug. 16 1949 UNITED STATES OrF'Fl '1' i sa ience. T 1 1 cAM-Ac'r r n,onlegnmcnawnnnonf iJohn Ii -(Alexander, San Diego, Calif. Anplic i nFebruaryl,1946, serial Nouoigeoz, '1 Claim. (alien-11c) v y (Granted under the act of March a 1sss, ,-;5s

This. invention relatesi more particularly to positive action wrenches.

An object of the invention is to provide an improved wrench device of such construction as to facilitate the installation and removal of relatively inaccessible articles or articles incapable of being removed by conventional wrenches.

Other objects of the invention are to provide an improved wrench device having positive action means for engaging a screw-threaded article to permit installation and removal of the article by rotation of the wrench device; to provide a wrench device, of thecharacter described, having gripping means adapted to be moved radially into and out of positive engagement with an inaccessible article for installing or removing the same without damage thereto; and to provide improved elements and arrangements thereof in a wrench device of the character described and for the purposes set forth.

In accomplishing these and other objects of the present invention, I have provided improved de-' tails of structure, the preferred form of which is illustrated in the accompanying drawing, where- Fig. 1 is a side elevational view, partly in section, of a wrench device embodying the features of the present invention.

Fig. 2 is a top plan view of the wrench device.

Referring more in detail to the drawing:

In Fig. 1, the numeral I designates a wrench device which includes a hollow, cylindrical body or sleeve 2, of metal or other suitable material. An externally screw-threaded radial enlargement or portion 3 is formed on the body 2 adjacent one end thereof for receiving an internally screw-threaded ring or annular nut 4. The inner peripheral end of the nut 4 is tapered to provide an external, bevelled shoulder 5, while the opposite end ofsaid nut is knurled externally as at 6 to facilitate rotation thereof. A circular disc or cap 1, having an axial, square or polygonal socket or opening 8, as most clearly shown in Fig. 2, is preferably press fitted within the end of the body externally of the nut and is fixedly secured thereto by short radial pins 9 or other suitable means so as to close said body end.

For pivotally supportin gripping elements or fingers I0, a pair of channel-shaped bars or brackets l l are secured to the exterior of the body 2 in longitudinal, diametrically-opposed relation. The brackets II are directed outwardly and extend from the open end of the body to a point substantially midway of its ends. A pivot pin l2 extends transversely across the inner end of each 'Q amended April- 30, 1928;; 3700.-

to wrench devices and bracket for. suspending; one of; the fingers 1' t0; V 1 1h? outer end of each finger projects a slight distance beyond the open end of the body and has an inwardly-directed, radial projection or lug l3- formed thereon. For urgingthe finger lugs l3 outwardly of the body, a coiled or spiraled compression spring I4 is confined between the outer end portions of each bracket and its finger. The upper ends of the fingers are provided with bevelled or tapered inner surface l5 complementary to the shoulder 5 of the nut 4, whereby clockwise rotation of said nut pivots said finger to swing,

the lugs inwardly of the body.

Operation The operation of a wrench device constructed as described is as follows:

The'wrench device I is adapted to be employed in installing and removing articles (not shown) which are relatively inaccessible or which are incapable of being rotated by wrenches of conventional construction.

In use, the body 2 is telescoped over the article after the nut 4 has been rotated in a counterclockwise direction so as to dispose the finger lugs I3 outwardly of the bore of said body due to the outward pressure exerted by the springs l4 upon the outer end portions of the fingers Ill. The lugs are adapted to be aligned with complementary recesses or openings (not shown) formed in the article to be installed or removed. Upon clockwise rotation of the nut, the coaction of its shoulder 5 with the finger surfaces l5 causes pivoting of the fingers so as to swing the lugs thereof inwardly of the body and into engagement with the recesses or openings of the article. With the body locked to the article, the same may be installed or removed by inserting a suitable tool (not shown) in the opening 8 of the cap I and rotating said body, In order to detach the body from the article, the nut is again rotated in a counter-clockwise direction so as to permit the pressure of the springs to pivot the fingers and disengage the lugs thereof from said article.

While I have shown but one embodiment of my invention, I do not wish to be limited by the disclosures set forth, but only by the scope of the appended claim.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

I claim: 7

A wrench device, including, a cylindrical hol- 3 brackets secured to the exterior of the body in diametric relation, the brackets being directed outwardly and extending longitudinally of said body from one end to a point intermediate its ends, a finger pivotally mounted at the inner end of each bracket and projecting beyond the ends thereof each finger being of sufficient width to substantially span the bracket, a compression spring interposed between the outer end portions of each bracket and its finger for resiliently maintaining the outer ends of the fingers outwardly of the body, an inwardly-directed radial lug formed on the outer end of each finger, the end portion of said body opposite the finger lugs being externally screw-threaded, an annular nut threadedly engaged upon the screw-threaded end of the body, an external bevelled shoulder formed on the outer end of the nut, the inner ends of the fingers being bevelled complementary to the shoulder and adapted to coact therewith upon rotation of said nut in one direction so as to pivot said finger lugs inwardly, and a cap mounted in the end of said body adjacent the nut, the cap having a polygonal opening for facilitating rotation of the body.

JOHN B. ALEXANDER.

REFERENCES CITED The following-references are of record in the file of this patent:

Great Britain .May 29, 1919 

